The proverb he who sups with the devil should have a long spoon is used especially to urge someone dealing with a person of this type to take care.
RELATED IDIOMS :
between the devil and the deep blue sea
caught in a dilemma
trapped between two equally dangerous alternatives
devil may care
cheerfully or defiantly reckless
a devil of a = the devil of a
something very large or bad of its kind – informal
1919 - Katherine Mansfield - LETTER - We had the devil of a great storm last night, lasting for hours, thunder, lightning, rain & I had appalling nightmares!
the devil's in the detail
the details of a matter are its most tricky or problematic aspect
the devil's own
a very difficult or great ______ - informal
1991 - Mavis Nicholson - Martha Jane & Me - It was the devil's own job to get her to give me some money for savings.
the devil to pay
serious trouble to be expected
This expression refers to the bargain formerly supposed to be made between magicians and the devil, the former receiving extraordinary powers or wealth in return for their souls.
give the devil his due
if someone or something generally considered bad or undeserving has any redeeming features these should be acknowledged – proverb
like the devil = like a demon
with great speed or energy
play devil's advocate
take a side in an argument that is the opposite of what you really want or think
A translation of the Latin phrase advocatus diaboli, devil's advocate is the popular name for the official in the Roman Catholic Church who puts the case against a candidate for canonization or beatification.
He is more properly known as promoter fidei promoter of the faith.
1994 - Jude Deveraux - The Invitation - She had played devil's advocate with herself a thousand times.
play the devil with = play Old Harry with
damage or affect greatly
Old Harry has been a nickname for the j devil in northern England since the 18th century.
raise the devil
make a noisy disturbance – informal
sell your soul = sell your soul to the devil
do or be willing to do anything, no matter how wrong, in order to achieve your objective.
The reference here is to a contract supposedly made with the devil by certain people. In return for granting them all their desires in this life, the devil would receive their souls for all eternity. The most famous person reputed to have entered into such a contract was the 16th-century German astronomer and necromancer Faust who became the subject of plays by Goethe and Marlowe and a novel by Thomas Mann.
speak of the devil = talk of the devil
said when a person appears just after being mentioned.
This phrase stems from the superstition that the devil will manifest himself if his name is spoken.